Oh is that how transitioning a door with IS works? In this video (2:05) I seemed to be going the opposite way that you'd need to?

Also that standing IS thing can be activated by using moon jump on Metroid Prime Wii and just holding it against a ceiling. As far as I know it's yet to happen ever on a vanilla version of the game so I'm not sure if it's actually something that could be taken advantage of.

So back in 2007 I bought a capture card to record a bunch of videos for a website I was part of at the time called Metroid Headquarters for the guy that worked there, Elias. The idea was to have a section emulating Metroid 2002's coverage of the game, while staying mostly up to date and introducing new things that had been discovered but hadn't been added to metroid2002. Anyway, it never got finished but I just have 4gb of Metroid Prime videos on my hard drive from when I was in grade 7 and trying to recreate the entirety of one of the most popular speed gaming websites of its time, plus a whole bunch of other new things. As a highlight, it includes the first ever recorded Vent Shaft under 21% conditions:

I have no clue how this happened and had no way to record it but in the room where you get boost ball I was jumping across the platforms to get it when the platforms just randomly disappeared (this was on the trilogy version)

Yes the platforms fall and break as you jump across them when you do the usual puzzle associated with Boost, fully disappearing after jumping on all of them to get Boost so you have a reason to try it out on the half-pipe.

Off the top of my head, IBBF and the current double IS route have the two most convenient ways of getting world without having to detour too much. IBBF however loses time as you have to fight the Chozo Ghost, not to mention you probably need to pass through late Chozo Ruins again to get to X-Ray Visor.

Hmm, maybe this could be a route change on Prime Wii though? (assuming Early World is possible on Wii)